US20120241302A1 - Push-on switch - Google Patents
Push-on switch Download PDFInfo
- Publication number
- US20120241302A1 US20120241302A1 US13/372,533 US201213372533A US2012241302A1 US 20120241302 A1 US20120241302 A1 US 20120241302A1 US 201213372533 A US201213372533 A US 201213372533A US 2012241302 A1 US2012241302 A1 US 2012241302A1
- Authority
- US
- United States
- Prior art keywords
- contact plate
- contact
- switch
- push
- projection
- Prior art date
- Legal status (The legal status is an assumption and is not a legal conclusion. Google has not performed a legal analysis and makes no representation as to the accuracy of the status listed.)
- Granted
Links
Images
Classifications
-
- H—ELECTRICITY
- H01—ELECTRIC ELEMENTS
- H01H—ELECTRIC SWITCHES; RELAYS; SELECTORS; EMERGENCY PROTECTIVE DEVICES
- H01H13/00—Switches having rectilinearly-movable operating part or parts adapted for pushing or pulling in one direction only, e.g. push-button switch
- H01H13/70—Switches having rectilinearly-movable operating part or parts adapted for pushing or pulling in one direction only, e.g. push-button switch having a plurality of operating members associated with different sets of contacts, e.g. keyboard
- H01H13/84—Switches having rectilinearly-movable operating part or parts adapted for pushing or pulling in one direction only, e.g. push-button switch having a plurality of operating members associated with different sets of contacts, e.g. keyboard characterised by ergonomic functions, e.g. for miniature keyboards; characterised by operational sensory functions, e.g. sound feedback
- H01H13/85—Switches having rectilinearly-movable operating part or parts adapted for pushing or pulling in one direction only, e.g. push-button switch having a plurality of operating members associated with different sets of contacts, e.g. keyboard characterised by ergonomic functions, e.g. for miniature keyboards; characterised by operational sensory functions, e.g. sound feedback characterised by tactile feedback features
-
- H—ELECTRICITY
- H01—ELECTRIC ELEMENTS
- H01H—ELECTRIC SWITCHES; RELAYS; SELECTORS; EMERGENCY PROTECTIVE DEVICES
- H01H2203/00—Form of contacts
- H01H2203/004—Rivet
-
- H—ELECTRICITY
- H01—ELECTRIC ELEMENTS
- H01H—ELECTRIC SWITCHES; RELAYS; SELECTORS; EMERGENCY PROTECTIVE DEVICES
- H01H2215/00—Tactile feedback
- H01H2215/004—Collapsible dome or bubble
- H01H2215/018—Collapsible dome or bubble unstressed in open position of switch
Definitions
- the present invention relates to a push-on switch to be used in an operating section of a variety of electronic devices.
- FIG. 8 is a sectional view of the conventional push-on switch
- FIG. 9 is an exploded perspective view of the conventional push-on switch
- FIG. 10 is a sectional view illustrating the conventional push-on switch depressed.
- Housing 1 is made of synthetic resin and includes an opening at the top face.
- center fixed contact 2 made of metal and two outer fixed contacts 3 made of metal and disposed symmetrically relative to center fixed contact 2 .
- center fixed contact 2 is interposed between the two outer fixed contacts 3 .
- Terminal 2 A connected to center contact 2 and terminal 3 A connected to outer fixed contacts 3 are led outside housing 1 .
- Movable contact 4 is made of elastic thin metal plate and forms a dome bowing upward.
- the underside of movable contact 4 is surface-treated for good electrical conductivity.
- Movable contact 4 is accommodated in the recess of housing 1 , and a lower end of the rim of movable contact 4 is seated on outer fixed contacts 3 .
- the center section of underside of movable contact 4 faces the top face of center fixed contact 2 with a space therebetween.
- Protective sheet 5 is formed by applying pressure-sensitive adhesive (not shown) onto the underside of an insulating film, and protective sheet 5 is fixed on housing 1 with the adhesive such that sheet 5 can cover the top face of the recess of housing 1 .
- the conventional push-on switch is constructed as discussed above. The operation of this switch is described hereinafter.
- depressing force is applied from above protective sheet 5 to the center section of domed (bowing upward) movable contact 4 , and when the depressing force exceeds a given level, the center section of movable contact 4 elastically reverses (protruding downward or bowing downward) with tactile click-feel as shown in FIG. 9 .
- Movable contact 4 then touches center fixed contact 2 with the center section of the underside of movable contact 4 .
- Outer fixed contacts 3 become electrically conductive to center fixed contact 2 via movable contact 4 , so that terminals 2 A and 3 A corresponding respectively to center contact 2 and outer contacts 3 fall into a switch-on state.
- Housing 1 of the foregoing conventional push-on switch is formed by insert-molding the center fixed contact 2 , outer fixed contacts 3 , and terminals 2 A and 3 A together, where terminals 2 A and 3 A correspond to contact 2 and contacts 3 .
- This structure tends to invite a shortage of synthetic resin at a thin-wall section in a case where the thickness of housing 1 is reduced, so that it is difficult to further downsize housing 1 or reduce the thickness of housing 1 .
- the present invention aims to provide a small size push-on switch that adopts an innovative structure in the member corresponding to the housing of a conventional switch for reducing the thickness, and on top of that, the push-on switch is excellent in contact stability while it is operated.
- the push-on switch of the present invention has a first contact plate, a second contact plate, a spacer, a movable contact, and a lid.
- the first contact plate includes a projection at the center and a first terminal at the end thereof.
- the second contact plate faces a face of the first contact plate protruding the projection, and the second contact plate includes an opening at the center and a second terminal at the end thereof.
- the spacer is interposed between the first contact plate and the second contact plate for bonding them together.
- the movable contact forms a dome, includes a protrusion protruding downward, and this protrusion faces the projection of the first contact plate via the opening with a given space therebetween.
- the lid holds the movable contact and is mounted on the top face of the second contact plate such that a push onto the movable contact reverses the movable contact downward and the protrusion can be brought into contact with the projection.
- a housing, outer fixed contacts, center fixed contact of the conventional push-on switch are changed into a laminated structure, i.e. two sheets of contact plates made of conductive thin metal sheet are bonded to a spacer placed therebetween so that the two sheets are bound together.
- This structure allows obtaining a low-profile push-on switch of which thickness can be reduced in response to each thickness of the two contact plates and the spacer.
- FIG. 1 shows an appearance of a push-on switch in accordance with an embodiment of the present invention.
- FIG. 2 is an exploded perspective view of the push-on switch in accordance with an embodiment of the present invention.
- FIG. 3 is a sectional view of the push-on switch in accordance with an embodiment of the present invention.
- FIG. 4 is a sectional view cut along a place including a slit of the push-on switch in accordance with an embodiment of the present invention.
- FIG. 5 is a sectional view enlarging the slit of the push-on switch in accordance with an embodiment of the present invention.
- FIG. 6 is a sectional view of the push-on switch, when it is depressed, in accordance with an embodiment of the present invention.
- FIG. 7 is a partial exploded perspective view of another push-on switch in accordance with an embodiment of the present invention.
- FIG. 8 is a sectional view of a conventional push-on switch.
- FIG. 9 is an exploded perspective view of the conventional push-on switch.
- FIG. 10 is a sectional view of the conventional push-on switch when it is depressed.
- FIG. 1 shows an appearance of a push-on switch in accordance with the embodiment of the present invention.
- FIG. 2 is an exploded perspective view of the push-on switch in accordance with the embodiment of the present invention.
- FIG. 3 is a sectional view of the push-on switch in accordance with the embodiment of the present invention.
- FIG. 4 is a sectional view cut along a place including a slit of the push-on switch in accordance with the embodiment of the present invention.
- FIG. 5 is a sectional view enlarging the slit of the push-on switch in accordance with the embodiment of the present invention.
- FIG. 6 is a sectional view of the push-on switch, when it is depressed, in accordance with the embodiment of the present invention.
- Push-on switch 100 includes first contact plate 11 , second contact plate 12 , spacer 13 , movable contact 14 , and protective sheet 15 working as a lid.
- First contact plate 11 has projection 11 B at the center and first terminals 11 A at the ends thereof.
- Second contact plate 12 faces a face of first contact plate 11 protruding projection 11 B and has opening 12 B at the center and second terminals 12 A at the ends thereof.
- Spacer 13 is interposed between first contact plate 11 and second contact plate 12 for bonding plate 11 and plate 12 together.
- Movable contact 14 forms a domed shape and has protrusions 14 A protruding downward.
- Movable contact 14 is brought into contact with a top face of second contact plate 12 , and protrusions 14 A face to projection 11 B of first contact plate 11 via opening 12 B with a given space therebetween.
- Protective sheet 15 holds movable contact 14 and is mounted onto the top face of second contact plate 12 .
- Protrusions 14 A are disposed in a position to come into contact with projection 11 B when movable contact 14 is pushed and reversed downward.
- First contact plate 11 is made of good-conductive metal sheet, e.g. a stainless steel sheet silver-plated on both the faces, and forms like a rectangular plate. Each one of first terminals 11 A protrudes outward from the two sides opposite to each other of first contact plate 11 . First terminals 11 A are placed at the ends of the two sides line-symmetrically. First contact plate 11 includes projection 11 B embossed upward at the center of plate 11 and shaped like a truncated cone.
- Second contact plate 12 is made of good-conductive metal sheet, e.g. a stainless steel sheet silver-plated on both the faces, and forms like a rectangular plate. Second contact plate 12 disposed opposite to first contact plate 11 , and has circular opening 12 B, at the center, having a greater diameter than that of a top face of projection 11 B. Second contact plate 12 has two second terminals 12 A disposed line-symmetrically with the two first terminals 11 A and protruding outward. First terminals 11 A are bent at their roots toward second contact plate 12 , and second terminals 12 A are also bent at their roots toward first contact plate 11 .
- Spacer 13 forms a film-like rectangular plate, and is made of LCP resin (Liquid Crystal Polymer) and is disposed between first contact plate 11 and second contact plate 12 .
- Spacer 13 has circular opening 13 A at the center, and opening 13 A forms the same shape as or a smaller shape than opening 12 B of second contact plate 12 , and has a diameter greater than that of the top face of projection 11 B.
- Spacer 13 is provided at an entire section, where first contact plate 11 overlap with second contact plate 12 , viewed from the top, thereby maintaining the insulation between first contact plate 11 and second contact plate 12 .
- the top face and the underside of spacer 13 are bonded to first contact plate 11 and second contact plate 12 respectively.
- first contact plate 11 , spacer 13 , and second contact plate 12 are layered in this order from the bottom, so that they can be integrated into one body.
- first contact plate 11 , spacer 13 , and second contact plate 12 are integrated into one body without using adhesive.
- Second contact plate 12 integrated with first contact plate 11 has two cut-away sections 12 D at two corners close to first terminals 11 A.
- first contact plate 11 has two cut-away sections (not shown) at two corners close to second terminals 12 A.
- the presence of cut-away sections 12 D allows preventing a short between first terminals 11 A and second contact plate 12 when push-on switch 100 is mounted to a printed circuit board by soldering. A short between second terminals 12 A and first contact plate 11 thus can be also prevented. Since the LCP resin of spacer 13 is softened by the thermo-compression, it flows into these cut-away sections 12 D, and then hardens there.
- First contact plate 11 viewed from the top is smaller than second contact plate 12 .
- This structure allows the LCP resin softened to flow in the periphery of plate 11 and then it hardens there, as the LCP resin does in cut-away sections 12 D.
- This structure allows maintaining the insulation after the assembly more steadily between plate 11 and plate 12 at the peripheries.
- first contact plate 11 is smaller than second contact plate 12 viewed from the top; however, contrary to this structure, second contact plate 12 can be smaller than first contact plate 11 with the same advantage as discussed previously.
- Spacer 13 can be made of other type of resin than the LCP resin, for instance, thermoplastic resin such as 9T nylon or PPS (Poly Phenylene Sulfide).
- Movable contact 14 is made of elastic thin metal sheet of which underside is surface-treated for good-conductivity, and forms a round dome bowing upward or projecting upward.
- three protrusions 14 A spherically formed are placed along a virtual circle having a center at the center of movable contact 14 , and three protrusions 14 A are placed at intervals of 120° and protrude downward.
- movable contact 14 forms a circle viewed from the top; however, it can be an oval or a polygon such as a rectangular shape.
- the shape, placement, and the number of protrusions 14 A are not limited to specific ones, but multiple protrusions 14 A as prepared in this embodiment are preferable because steady contact at multi-points can be produced by a switch operation.
- Movable contact 14 is placed directly on second contact plate 12 and its underside at the center faces to the top face of first contact plate 11 via opening 12 B of second contact plate 12 and opening 13 A of spacer 13 .
- Projection 11 B shaped like a truncated cone has a top face of which diameter is somewhat greater than that of the virtual circle along which three protrusions 14 A are placed.
- this structure allows protrusions 14 A to touch projection 11 B at a rim of the top face close to the slanting face forming a sidewall of projection 11 B, that is to say the structure allows protrusion 14 A to touch projection 11 B at a vicinity of a rim of the top face of the projection 11 B.
- protrusions 14 A and projection 11 B can be on the slanting face of the sidewall of projection 11 B.
- This structure allows protrusions 14 A to be supported indirectly by the sidewall of projection 11 B, so that even if switch 100 is pushed repeatedly, projection 11 B scarcely encounters a cave-in.
- a height of projection 11 B and heights of protrusions 14 A can be determined appropriately so that the distance between the contacts can be set properly with ease.
- Protective sheet 15 is made of insulating and rectangular film and includes adhesive layer 16 on the entire underside. Adhesive layer 16 thus allows protective sheet 15 to be mounted rigidly onto the top face of second contact plate 12 , so that protective sheet 15 works as a lid. Adhesive layer 16 also holds and positions movable contact 14 onto second contact plate 12 .
- Protective sheet 15 preferably employs heat-resistant insulating film, e.g. polyimide resin.
- Adhesive layer 16 preferably employs heat-resistant acrylic-based adhesive agent.
- rectangular protective sheet 15 is employed; however, the shape of sheet 15 can be appropriately selected depending on the shape and size of the switch. As discussed above, use of protective sheet 15 having adhesive layer 16 allows protective sheet 15 to solidly stick onto second contact plate 12 with ease.
- Protective sheet 15 can be made of the LCP resin as spacer 13 is. In this case, protective sheet 15 can be mounted onto second contact plate by thermo-compression instead of using adhesive layer 16 .
- an air opening is preferably provided for communicating between the outside and the inside of movable contact 14 .
- second contact plate 12 is preferably provided with slit 12 C, which works as the air opening, starting from an edge of the periphery toward opening 12 B.
- Slit 12 C forms a linear shape having a width of approx. 0.15 mm, and its tip forms an arc.
- the length of slit 12 C is determined such that it runs from inside of the lower end of the rim of movable contact 14 until before it reaches opening 12 B.
- the air trapped in the space covered by the underside of movable contact 14 can flow outward through slit 12 C from the vicinity of inside of the lower end of the rim of movable contact 14 .
- This structure allows preventing slowdown of the tactile click-feel of the switch when movable contact 14 stays in a compressed state or in a negative pressure state in response to the operation of the movable contact 14 , because the air trapped in movable contact 14 can flow out or flow in through the air opening formed of slit 12 C.
- Slit 12 C can reach opening 12 B; however, the foregoing structure, i.e. slit 12 C ends before it reaches opening 12 B, prevents second contact plate 12 from twisting at slit 12 C during the manufacturing process, so that the productivity can be improved.
- the push-on switch in accordance with the embodiment is thus structured as discussed previously.
- the operation of this switch is demonstrated hereinafter.
- a user pushes the switch from the top, and depressing force is applied to the center of protective sheet 15 .
- This depressing force is given to the top of domed movable contact 14 .
- the center of the domed shape of movable contact 14 reverses elastically and bows downward (protrudes downward) with tactile click-feel as shown in FIG. 6 .
- protrusions 14 A formed at the center of movable contact 14 touch the top face of projection 11 B, existing below and facing to protrusions 14 A, of first contact plate 11 .
- This mechanism generates electrical conductivity between second contact plate 12 and first contact plate 11 via movable contact 14 , so that a switch-on state is produced between second terminal 12 A and first terminal 11 A.
- the air trapped within movable contact 14 is compressed by the push, and then flows outward through slit 12 C from the vicinity of the inside of the lower end of the rim of movable contact 14 .
- the reversing action of movable contact 14 makes the compressed air flow outward, so that the reversing action gives the user a good tactile click-feel free from interference by the compressed air.
- movable contact 14 When the user removes his/her finger from the switch, i.e. removes the depressing force, movable contact 14 is restored elastically to the original domed shape, bowing upward (protruding upward), by self-resetting force with tactile click-feel. Then a switch-off state is produced between second terminal 12 A and first terminal 11 A.
- the restoring action enlarges a cubic volume in movable contact 14 , so that the inside thereof becomes a negative pressure state. This mechanism allows the air outside the switch to flow into movable contact 14 via slit 12 C from the lower end of the rim of movable contact 14 .
- the push-on switch in accordance with the embodiment forms a simple laminated structure in which first contact plate 11 , spacer 13 , second contact plate 12 are integrated together into one body that corresponds to the housing of the conventional push-on switch. Reduction in thickness of first contact plate 11 , spacer 13 , and second contact plate 12 respectively thus allows reducing the thickness of the push-on switch with ease.
- the conventional switch needs an outer wall for housing 1 in order to form a recess; however, the embodiment adopts the structure where movable contact 14 is disposed on second contact plate 12 , so that no outer wall is needed. This structure thus allows downsizing the switch for that.
- slit 12 C forms the air opening that allows air to travel between the inside and the outside of movable contact 14 .
- This structure allows the air trapped inside movable contact 14 to flow out and flow in via the air opening, for movable contact 14 falls into a compressed state or a negative pressure state in response to the operation. As a result, the air inside movable contact 14 does not affect so much the operation of movable contact 14 , and thus good tactile click-feel can be obtained.
- the air opening is not necessarily a slit 12 C, i.e. formed by cutting second contact plate 12 , but it can be a groove formed depth-wise on second contact plate 12 , or a similar slit can be formed on spacer 13 instead of second contact plate 12 , and this slit can be used as the air opening.
- Any of these structures allows the air trapped inside movable contact 14 to flow out and flow in via the air opening, for movable contact 14 falls into a compressed state or a negative pressure state in response to the operation. As a result, the air inside movable contact 14 does not affect so much the operation of movable contact 14 , and thus good tactile click-feel can be obtained.
- Slit 12 C does not reach opening 12 B, is preferable because it prevents more effectively dust from entering movable contact 14 than a structure where slit 12 C reaches opening 12 B.
- Slit 12 C is not always a linear shape but it can be a bent shape or a curve.
- a cylindrical protrusion to be pressed can be formed on the top face of protective sheet 15 .
- This protrusion is placed corresponding to the center of domed movable contact 14 , and is made of, e.g. insulating resin such as polyimide resin.
- the protrusion can be fixed on the top face of protective sheet 15 with adhesive of thermosetting or ultraviolet-ray setting, or the protrusion can be unitarily formed with protective sheet 15 . Even if the center of operating button of an electronic device is somewhat deviated from the center of the push switch mounted to the electronic device, e.g. a portable phone, this structure allows the movable contact to be pushed at its center via the protrusion to be pressed, so that the user can always get good tactile click-feel.
- Projection 11 B formed on first contact plate 11 is preferably shaped like truncated cone because it can be formed with ease by embossing upward a sheet metal.
- the shape of projection 11 B can be cylindrical or a polygon viewed from the top. These shapes also produce an advantage similar to what is discussed previously.
- projection 11 C can be recessed at its center, in other words, it can form a ring shape viewed from the top. This shape allows supporting the touching points to protrusions 14 A not only by the outer wall but also by the inner side indirectly, so that the strength of projection 11 C can be further increased. This structure allows preventing more effectively projection 11 C from a cave-in and maintaining a stable contact, when the switch is pushed, for an extended period of use.
- First contact plate 11 and second contact plate 12 are not always made of stainless steel sheet silver-plated, for instance, they can be made of silver-clad member as far as they are surface-treated for good conductivity and solderbility.
- the surface treatment is not necessarily provided to the entire surfaces, for instance, the surfaces of first terminal 11 A and second terminal 12 A can be surface-treated for good solderbility, and each center portion, i.e. the place carrying out the switch-contact function, of first contact plate 11 and second contact plate 12 , can be surface-treated for good conductivity.
- First and second terminals 11 A and 12 A can be curved like a letter “J”.
- Push-on switch 100 of the present invention is capable of being used in various electronic devices that are required to be downsized or to be thinner in shape, and push-on switch 100 is also excellent in stability of contact when it is operated. Push-on switch 100 is thus useful for operating a variety of electronic devices.
Landscapes
- Push-Button Switches (AREA)
Abstract
Description
- The present invention relates to a push-on switch to be used in an operating section of a variety of electronic devices.
- In recent years, a variety of electronic devices has been downsized, light-weighted, and yet sophisticated. This market trend also requires downsizing of push-on switches to be used at operating sections of the electronic devices.
- A conventional push-on switch is described hereinafter with reference to
FIG. 8-FIG . 10.FIG. 8 is a sectional view of the conventional push-on switch, andFIG. 9 is an exploded perspective view of the conventional push-on switch.FIG. 10 is a sectional view illustrating the conventional push-on switch depressed.Housing 1 is made of synthetic resin and includes an opening at the top face. On a recessed inner bottom face ofhousing 1, there are center fixedcontact 2 made of metal and two outerfixed contacts 3 made of metal and disposed symmetrically relative to center fixedcontact 2. In other words, center fixedcontact 2 is interposed between the two outerfixed contacts 3.Terminal 2A connected tocenter contact 2 andterminal 3A connected to outerfixed contacts 3 are led outsidehousing 1. -
Movable contact 4 is made of elastic thin metal plate and forms a dome bowing upward. The underside ofmovable contact 4 is surface-treated for good electrical conductivity.Movable contact 4 is accommodated in the recess ofhousing 1, and a lower end of the rim ofmovable contact 4 is seated on outerfixed contacts 3. The center section of underside ofmovable contact 4 faces the top face of center fixedcontact 2 with a space therebetween. -
Protective sheet 5 is formed by applying pressure-sensitive adhesive (not shown) onto the underside of an insulating film, andprotective sheet 5 is fixed onhousing 1 with the adhesive such thatsheet 5 can cover the top face of the recess ofhousing 1. - The conventional push-on switch is constructed as discussed above. The operation of this switch is described hereinafter. First, depressing force is applied from above
protective sheet 5 to the center section of domed (bowing upward)movable contact 4, and when the depressing force exceeds a given level, the center section ofmovable contact 4 elastically reverses (protruding downward or bowing downward) with tactile click-feel as shown inFIG. 9 .Movable contact 4 then touches center fixedcontact 2 with the center section of the underside ofmovable contact 4. Outerfixed contacts 3 become electrically conductive to centerfixed contact 2 viamovable contact 4, so thatterminals contact 2 andouter contacts 3 fall into a switch-on state. - When the depressing force is removed, the center section of
movable contact 4 elastically restores to the original shape, i.e. bowing upward, with tactile click-feel, andmovable contact 4 leaves center fixedcontact 2 at the center of the underside ofmovable contact 4. Theterminals - Prior arts related to the present invention include the Japanese Patent Unexamined Publications No. 2003-297175 and No2002-63823.
-
Housing 1 of the foregoing conventional push-on switch is formed by insert-molding the center fixedcontact 2, outerfixed contacts 3, andterminals terminals contact 2 andcontacts 3. This structure tends to invite a shortage of synthetic resin at a thin-wall section in a case where the thickness ofhousing 1 is reduced, so that it is difficult to further downsizehousing 1 or reduce the thickness ofhousing 1. - The present invention aims to provide a small size push-on switch that adopts an innovative structure in the member corresponding to the housing of a conventional switch for reducing the thickness, and on top of that, the push-on switch is excellent in contact stability while it is operated.
- The push-on switch of the present invention has a first contact plate, a second contact plate, a spacer, a movable contact, and a lid. The first contact plate includes a projection at the center and a first terminal at the end thereof. The second contact plate faces a face of the first contact plate protruding the projection, and the second contact plate includes an opening at the center and a second terminal at the end thereof. The spacer is interposed between the first contact plate and the second contact plate for bonding them together. The movable contact forms a dome, includes a protrusion protruding downward, and this protrusion faces the projection of the first contact plate via the opening with a given space therebetween. The lid holds the movable contact and is mounted on the top face of the second contact plate such that a push onto the movable contact reverses the movable contact downward and the protrusion can be brought into contact with the projection.
- A housing, outer fixed contacts, center fixed contact of the conventional push-on switch are changed into a laminated structure, i.e. two sheets of contact plates made of conductive thin metal sheet are bonded to a spacer placed therebetween so that the two sheets are bound together. This structure allows obtaining a low-profile push-on switch of which thickness can be reduced in response to each thickness of the two contact plates and the spacer.
-
FIG. 1 shows an appearance of a push-on switch in accordance with an embodiment of the present invention. -
FIG. 2 is an exploded perspective view of the push-on switch in accordance with an embodiment of the present invention. -
FIG. 3 is a sectional view of the push-on switch in accordance with an embodiment of the present invention. -
FIG. 4 is a sectional view cut along a place including a slit of the push-on switch in accordance with an embodiment of the present invention. -
FIG. 5 is a sectional view enlarging the slit of the push-on switch in accordance with an embodiment of the present invention. -
FIG. 6 is a sectional view of the push-on switch, when it is depressed, in accordance with an embodiment of the present invention. -
FIG. 7 is a partial exploded perspective view of another push-on switch in accordance with an embodiment of the present invention. -
FIG. 8 is a sectional view of a conventional push-on switch. -
FIG. 9 is an exploded perspective view of the conventional push-on switch. -
FIG. 10 is a sectional view of the conventional push-on switch when it is depressed. - An exemplary embodiment of the present invention is demonstrated hereinafter with reference to accompanying
FIG. 1-FIG . 6.FIG. 1 shows an appearance of a push-on switch in accordance with the embodiment of the present invention.FIG. 2 is an exploded perspective view of the push-on switch in accordance with the embodiment of the present invention.FIG. 3 is a sectional view of the push-on switch in accordance with the embodiment of the present invention.FIG. 4 is a sectional view cut along a place including a slit of the push-on switch in accordance with the embodiment of the present invention.FIG. 5 is a sectional view enlarging the slit of the push-on switch in accordance with the embodiment of the present invention.FIG. 6 is a sectional view of the push-on switch, when it is depressed, in accordance with the embodiment of the present invention. - Push-on switch 100 includes
first contact plate 11,second contact plate 12,spacer 13,movable contact 14, andprotective sheet 15 working as a lid.First contact plate 11 hasprojection 11B at the center andfirst terminals 11A at the ends thereof.Second contact plate 12 faces a face offirst contact plate 11 protrudingprojection 11B and has opening 12B at the center andsecond terminals 12A at the ends thereof.Spacer 13 is interposed betweenfirst contact plate 11 andsecond contact plate 12 forbonding plate 11 andplate 12 together.Movable contact 14 forms a domed shape and hasprotrusions 14A protruding downward.Movable contact 14 is brought into contact with a top face ofsecond contact plate 12, andprotrusions 14A face toprojection 11B offirst contact plate 11 via opening 12B with a given space therebetween.Protective sheet 15 holdsmovable contact 14 and is mounted onto the top face ofsecond contact plate 12.Protrusions 14A are disposed in a position to come into contact withprojection 11B whenmovable contact 14 is pushed and reversed downward. - Each one of the foregoing structural elements is detailed hereinafter.
First contact plate 11 is made of good-conductive metal sheet, e.g. a stainless steel sheet silver-plated on both the faces, and forms like a rectangular plate. Each one offirst terminals 11A protrudes outward from the two sides opposite to each other offirst contact plate 11.First terminals 11A are placed at the ends of the two sides line-symmetrically.First contact plate 11 includesprojection 11B embossed upward at the center ofplate 11 and shaped like a truncated cone. -
Second contact plate 12 is made of good-conductive metal sheet, e.g. a stainless steel sheet silver-plated on both the faces, and forms like a rectangular plate.Second contact plate 12 disposed opposite tofirst contact plate 11, and hascircular opening 12B, at the center, having a greater diameter than that of a top face ofprojection 11B.Second contact plate 12 has twosecond terminals 12A disposed line-symmetrically with the twofirst terminals 11A and protruding outward.First terminals 11A are bent at their roots towardsecond contact plate 12, andsecond terminals 12A are also bent at their roots towardfirst contact plate 11. -
Spacer 13 forms a film-like rectangular plate, and is made of LCP resin (Liquid Crystal Polymer) and is disposed betweenfirst contact plate 11 andsecond contact plate 12.Spacer 13 hascircular opening 13A at the center, and opening 13A forms the same shape as or a smaller shape than opening 12B ofsecond contact plate 12, and has a diameter greater than that of the top face ofprojection 11B.Spacer 13 is provided at an entire section, wherefirst contact plate 11 overlap withsecond contact plate 12, viewed from the top, thereby maintaining the insulation betweenfirst contact plate 11 andsecond contact plate 12. The top face and the underside ofspacer 13 are bonded tofirst contact plate 11 andsecond contact plate 12 respectively. In other words, as shown inFIG. 3 ,first contact plate 11,spacer 13, andsecond contact plate 12 are layered in this order from the bottom, so that they can be integrated into one body. - A method of manufacturing the foregoing push-on switch is demonstrated hereinafter. Hold
spacer 13 betweenfirst contact plate 11 andsecond contact plate 12, and then apply heat and pressure from underfirst contact plate 11 on whichprojection 11B has been formed, and also apply heat and pressure from abovesecond contact plate 12. This thermo-compression softensspacer 13 made of LCP resin and generates anchor effect, so that both the surfaces ofspacer 13 are rigidly bonded to the respective surfaces offirst contact plate 11 andsecond contact plate 12. As a result,first contact plate 11,spacer 13, andsecond contact plate 12 are integrated into one body without using adhesive. -
Second contact plate 12 integrated withfirst contact plate 11 has two cut-awaysections 12D at two corners close tofirst terminals 11A. In a similar way,first contact plate 11 has two cut-away sections (not shown) at two corners close tosecond terminals 12A. The presence of cut-awaysections 12D allows preventing a short betweenfirst terminals 11A andsecond contact plate 12 when push-on switch 100 is mounted to a printed circuit board by soldering. A short betweensecond terminals 12A andfirst contact plate 11 thus can be also prevented. Since the LCP resin ofspacer 13 is softened by the thermo-compression, it flows into these cut-awaysections 12D, and then hardens there. -
First contact plate 11 viewed from the top is smaller thansecond contact plate 12. This structure allows the LCP resin softened to flow in the periphery ofplate 11 and then it hardens there, as the LCP resin does in cut-awaysections 12D. This structure allows maintaining the insulation after the assembly more steadily betweenplate 11 andplate 12 at the peripheries. In this embodiment,first contact plate 11 is smaller thansecond contact plate 12 viewed from the top; however, contrary to this structure,second contact plate 12 can be smaller thanfirst contact plate 11 with the same advantage as discussed previously. -
Spacer 13 can be made of other type of resin than the LCP resin, for instance, thermoplastic resin such as 9T nylon or PPS (Poly Phenylene Sulfide). -
Movable contact 14 is made of elastic thin metal sheet of which underside is surface-treated for good-conductivity, and forms a round dome bowing upward or projecting upward. At the center of underside ofmovable contact 14, threeprotrusions 14A spherically formed are placed along a virtual circle having a center at the center ofmovable contact 14, and threeprotrusions 14A are placed at intervals of 120° and protrude downward. In this embodiment,movable contact 14 forms a circle viewed from the top; however, it can be an oval or a polygon such as a rectangular shape. The shape, placement, and the number ofprotrusions 14A are not limited to specific ones, butmultiple protrusions 14A as prepared in this embodiment are preferable because steady contact at multi-points can be produced by a switch operation. -
Movable contact 14 is placed directly onsecond contact plate 12 and its underside at the center faces to the top face offirst contact plate 11 viaopening 12B ofsecond contact plate 12 andopening 13A ofspacer 13.Projection 11B shaped like a truncated cone has a top face of which diameter is somewhat greater than that of the virtual circle along which threeprotrusions 14A are placed. Whenmovable contact 14 is elastically reversed, this structure allowsprotrusions 14A to touchprojection 11B at a rim of the top face close to the slanting face forming a sidewall ofprojection 11B, that is to say the structure allowsprotrusion 14A to touchprojection 11B at a vicinity of a rim of the top face of theprojection 11B. - The touch points between
protrusions 14A andprojection 11B can be on the slanting face of the sidewall ofprojection 11B. This structure allowsprotrusions 14A to be supported indirectly by the sidewall ofprojection 11B, so that even if switch 100 is pushed repeatedly,projection 11B scarcely encounters a cave-in. A height ofprojection 11B and heights ofprotrusions 14A can be determined appropriately so that the distance between the contacts can be set properly with ease. -
Protective sheet 15 is made of insulating and rectangular film and includesadhesive layer 16 on the entire underside.Adhesive layer 16 thus allowsprotective sheet 15 to be mounted rigidly onto the top face ofsecond contact plate 12, so thatprotective sheet 15 works as a lid.Adhesive layer 16 also holds and positionsmovable contact 14 ontosecond contact plate 12.Protective sheet 15 preferably employs heat-resistant insulating film, e.g. polyimide resin.Adhesive layer 16 preferably employs heat-resistant acrylic-based adhesive agent. In this embodiment, rectangularprotective sheet 15 is employed; however, the shape ofsheet 15 can be appropriately selected depending on the shape and size of the switch. As discussed above, use ofprotective sheet 15 havingadhesive layer 16 allowsprotective sheet 15 to solidly stick ontosecond contact plate 12 with ease.Protective sheet 15 can be made of the LCP resin asspacer 13 is. In this case,protective sheet 15 can be mounted onto second contact plate by thermo-compression instead of usingadhesive layer 16. - On top of that, as shown in
FIGS. 2 , 4, and 5, an air opening is preferably provided for communicating between the outside and the inside ofmovable contact 14. To be more specific,second contact plate 12 is preferably provided withslit 12C, which works as the air opening, starting from an edge of the periphery towardopening 12B.Slit 12C forms a linear shape having a width of approx. 0.15 mm, and its tip forms an arc. The length ofslit 12C is determined such that it runs from inside of the lower end of the rim ofmovable contact 14 until before it reaches opening 12B. In other words, the air trapped in the space covered by the underside ofmovable contact 14 can flow outward throughslit 12C from the vicinity of inside of the lower end of the rim ofmovable contact 14. This structure allows preventing slowdown of the tactile click-feel of the switch whenmovable contact 14 stays in a compressed state or in a negative pressure state in response to the operation of themovable contact 14, because the air trapped inmovable contact 14 can flow out or flow in through the air opening formed ofslit 12C. -
Slit 12C can reachopening 12B; however, the foregoing structure, i.e. slit 12C ends before it reaches opening 12B, preventssecond contact plate 12 from twisting atslit 12C during the manufacturing process, so that the productivity can be improved. - The push-on switch in accordance with the embodiment is thus structured as discussed previously. The operation of this switch is demonstrated hereinafter.
- First, a user pushes the switch from the top, and depressing force is applied to the center of
protective sheet 15. This depressing force is given to the top of domedmovable contact 14. When the depressing force exceeds a predetermined level, the center of the domed shape ofmovable contact 14 reverses elastically and bows downward (protrudes downward) with tactile click-feel as shown inFIG. 6 . Thenprotrusions 14A formed at the center ofmovable contact 14 touch the top face ofprojection 11B, existing below and facing to protrusions 14A, offirst contact plate 11. This mechanism generates electrical conductivity betweensecond contact plate 12 andfirst contact plate 11 viamovable contact 14, so that a switch-on state is produced between second terminal 12A andfirst terminal 11A. At this time, the air trapped withinmovable contact 14 is compressed by the push, and then flows outward throughslit 12C from the vicinity of the inside of the lower end of the rim ofmovable contact 14. In other words, the reversing action ofmovable contact 14 makes the compressed air flow outward, so that the reversing action gives the user a good tactile click-feel free from interference by the compressed air. - When the user removes his/her finger from the switch, i.e. removes the depressing force,
movable contact 14 is restored elastically to the original domed shape, bowing upward (protruding upward), by self-resetting force with tactile click-feel. Then a switch-off state is produced between second terminal 12A andfirst terminal 11A. The restoring action enlarges a cubic volume inmovable contact 14, so that the inside thereof becomes a negative pressure state. This mechanism allows the air outside the switch to flow intomovable contact 14 viaslit 12C from the lower end of the rim ofmovable contact 14. - As discussed above, the push-on switch in accordance with the embodiment forms a simple laminated structure in which
first contact plate 11,spacer 13,second contact plate 12 are integrated together into one body that corresponds to the housing of the conventional push-on switch. Reduction in thickness offirst contact plate 11,spacer 13, andsecond contact plate 12 respectively thus allows reducing the thickness of the push-on switch with ease. - On top of that, the conventional switch needs an outer wall for
housing 1 in order to form a recess; however, the embodiment adopts the structure wheremovable contact 14 is disposed onsecond contact plate 12, so that no outer wall is needed. This structure thus allows downsizing the switch for that. - The presence of
slit 12C forms the air opening that allows air to travel between the inside and the outside ofmovable contact 14. This structure allows the air trapped insidemovable contact 14 to flow out and flow in via the air opening, formovable contact 14 falls into a compressed state or a negative pressure state in response to the operation. As a result, the air insidemovable contact 14 does not affect so much the operation ofmovable contact 14, and thus good tactile click-feel can be obtained. - The air opening is not necessarily a
slit 12C, i.e. formed by cuttingsecond contact plate 12, but it can be a groove formed depth-wise onsecond contact plate 12, or a similar slit can be formed onspacer 13 instead ofsecond contact plate 12, and this slit can be used as the air opening. Any of these structures allows the air trapped insidemovable contact 14 to flow out and flow in via the air opening, formovable contact 14 falls into a compressed state or a negative pressure state in response to the operation. As a result, the air insidemovable contact 14 does not affect so much the operation ofmovable contact 14, and thus good tactile click-feel can be obtained. - The structure discussed above, i.e. slit 12C does not reach opening 12B, is preferable because it prevents more effectively dust from entering
movable contact 14 than a structure where slit 12C reaches opening 12B.Slit 12C is not always a linear shape but it can be a bent shape or a curve. - Although it is not shown in the drawings, a cylindrical protrusion to be pressed can be formed on the top face of
protective sheet 15. This protrusion is placed corresponding to the center of domedmovable contact 14, and is made of, e.g. insulating resin such as polyimide resin. The protrusion can be fixed on the top face ofprotective sheet 15 with adhesive of thermosetting or ultraviolet-ray setting, or the protrusion can be unitarily formed withprotective sheet 15. Even if the center of operating button of an electronic device is somewhat deviated from the center of the push switch mounted to the electronic device, e.g. a portable phone, this structure allows the movable contact to be pushed at its center via the protrusion to be pressed, so that the user can always get good tactile click-feel. -
Projection 11B formed onfirst contact plate 11 is preferably shaped like truncated cone because it can be formed with ease by embossing upward a sheet metal. However, the shape ofprojection 11B can be cylindrical or a polygon viewed from the top. These shapes also produce an advantage similar to what is discussed previously. As shown inFIG. 7 ,projection 11C can be recessed at its center, in other words, it can form a ring shape viewed from the top. This shape allows supporting the touching points toprotrusions 14A not only by the outer wall but also by the inner side indirectly, so that the strength ofprojection 11C can be further increased. This structure allows preventing more effectivelyprojection 11C from a cave-in and maintaining a stable contact, when the switch is pushed, for an extended period of use. -
First contact plate 11 andsecond contact plate 12 are not always made of stainless steel sheet silver-plated, for instance, they can be made of silver-clad member as far as they are surface-treated for good conductivity and solderbility. The surface treatment is not necessarily provided to the entire surfaces, for instance, the surfaces offirst terminal 11A andsecond terminal 12A can be surface-treated for good solderbility, and each center portion, i.e. the place carrying out the switch-contact function, offirst contact plate 11 andsecond contact plate 12, can be surface-treated for good conductivity. First andsecond terminals - The expressions of directions used in this specification, e.g. up, down, left, and right, specify relative positional relations between the structural elements, and they do not specify absolute positional relations.
- Push-on switch 100 of the present invention is capable of being used in various electronic devices that are required to be downsized or to be thinner in shape, and push-on switch 100 is also excellent in stability of contact when it is operated. Push-on switch 100 is thus useful for operating a variety of electronic devices.
Claims (8)
Applications Claiming Priority (2)
Application Number | Priority Date | Filing Date | Title |
---|---|---|---|
JP2011063818A JP2012199182A (en) | 2011-03-23 | 2011-03-23 | Push-on switch |
JP2011-063818 | 2011-03-23 |
Publications (2)
Publication Number | Publication Date |
---|---|
US20120241302A1 true US20120241302A1 (en) | 2012-09-27 |
US8698028B2 US8698028B2 (en) | 2014-04-15 |
Family
ID=46859225
Family Applications (1)
Application Number | Title | Priority Date | Filing Date |
---|---|---|---|
US13/372,533 Expired - Fee Related US8698028B2 (en) | 2011-03-23 | 2012-02-14 | Push-on switch |
Country Status (3)
Country | Link |
---|---|
US (1) | US8698028B2 (en) |
JP (1) | JP2012199182A (en) |
CN (1) | CN102693852A (en) |
Cited By (4)
Publication number | Priority date | Publication date | Assignee | Title |
---|---|---|---|---|
US20140311882A1 (en) * | 2013-04-19 | 2014-10-23 | Mitsumi Electric Co., Ltd. | Switch |
USD741819S1 (en) * | 2013-03-26 | 2015-10-27 | Hokuriku Electric Industry Co., Ltd. | Push switch |
US10488954B1 (en) * | 2018-08-10 | 2019-11-26 | Primax Electronics Ltd. | SMD switch and touchpad module and computing device using same |
US10755876B2 (en) * | 2016-09-13 | 2020-08-25 | Panasonic Intellectual Property Management Co., Ltd. | Push switch |
Families Citing this family (3)
Publication number | Priority date | Publication date | Assignee | Title |
---|---|---|---|---|
TWI616916B (en) * | 2015-10-14 | 2018-03-01 | Alps Electric Co Ltd | Push-button switch and movable contact member |
CN109003855B (en) * | 2018-07-25 | 2020-08-28 | 高铭电子(惠州)有限公司 | Micro-switch |
CN111696807B (en) * | 2019-03-11 | 2023-03-24 | 富士康(昆山)电脑接插件有限公司 | Push-button switch |
Citations (5)
Publication number | Priority date | Publication date | Assignee | Title |
---|---|---|---|---|
US5828016A (en) * | 1996-02-12 | 1998-10-27 | Lucas Automation And Control Engineering, Inc. | Low profile tactile switch |
US6936777B1 (en) * | 2004-03-12 | 2005-08-30 | Fuji Electronics Industries Co., Ltd. | Two-step switch |
US20080164133A1 (en) * | 2004-06-15 | 2008-07-10 | Japan Aviation Electronice Industry Limited | Dome-Shaped Contact and Multi-Step Operation Electrical Switch Incorporating the Same |
US7589607B2 (en) * | 2003-09-17 | 2009-09-15 | Coactive Technologies, Inc | Thin contactor |
US20110089004A1 (en) * | 2009-10-15 | 2011-04-21 | Panasonic Corporation | Push-on switch |
Family Cites Families (6)
Publication number | Priority date | Publication date | Assignee | Title |
---|---|---|---|---|
JP3428248B2 (en) * | 1995-09-26 | 2003-07-22 | 松下電器産業株式会社 | Push-on switch |
JP2000149707A (en) * | 1998-11-06 | 2000-05-30 | Japan Aviation Electronics Industry Ltd | Dome contact switch |
JP4058892B2 (en) | 2000-08-22 | 2008-03-12 | 松下電器産業株式会社 | Push switch |
JP4085676B2 (en) | 2002-04-04 | 2008-05-14 | 松下電器産業株式会社 | Push-on switch |
JP4518989B2 (en) * | 2005-03-29 | 2010-08-04 | 帝国通信工業株式会社 | Press switch |
JP2007280616A (en) * | 2006-04-03 | 2007-10-25 | Alps Electric Co Ltd | Movable contact body for switch, and switching device |
-
2011
- 2011-03-23 JP JP2011063818A patent/JP2012199182A/en not_active Withdrawn
-
2012
- 2012-02-14 US US13/372,533 patent/US8698028B2/en not_active Expired - Fee Related
- 2012-03-20 CN CN2012100746643A patent/CN102693852A/en active Pending
Patent Citations (5)
Publication number | Priority date | Publication date | Assignee | Title |
---|---|---|---|---|
US5828016A (en) * | 1996-02-12 | 1998-10-27 | Lucas Automation And Control Engineering, Inc. | Low profile tactile switch |
US7589607B2 (en) * | 2003-09-17 | 2009-09-15 | Coactive Technologies, Inc | Thin contactor |
US6936777B1 (en) * | 2004-03-12 | 2005-08-30 | Fuji Electronics Industries Co., Ltd. | Two-step switch |
US20080164133A1 (en) * | 2004-06-15 | 2008-07-10 | Japan Aviation Electronice Industry Limited | Dome-Shaped Contact and Multi-Step Operation Electrical Switch Incorporating the Same |
US20110089004A1 (en) * | 2009-10-15 | 2011-04-21 | Panasonic Corporation | Push-on switch |
Cited By (4)
Publication number | Priority date | Publication date | Assignee | Title |
---|---|---|---|---|
USD741819S1 (en) * | 2013-03-26 | 2015-10-27 | Hokuriku Electric Industry Co., Ltd. | Push switch |
US20140311882A1 (en) * | 2013-04-19 | 2014-10-23 | Mitsumi Electric Co., Ltd. | Switch |
US10755876B2 (en) * | 2016-09-13 | 2020-08-25 | Panasonic Intellectual Property Management Co., Ltd. | Push switch |
US10488954B1 (en) * | 2018-08-10 | 2019-11-26 | Primax Electronics Ltd. | SMD switch and touchpad module and computing device using same |
Also Published As
Publication number | Publication date |
---|---|
CN102693852A (en) | 2012-09-26 |
US8698028B2 (en) | 2014-04-15 |
JP2012199182A (en) | 2012-10-18 |
Similar Documents
Publication | Publication Date | Title |
---|---|---|
US8698028B2 (en) | Push-on switch | |
KR101799065B1 (en) | Push switch and switch module | |
CN203983099U (en) | Key switch | |
TWI284337B (en) | Push-on switch | |
JP2010534899A (en) | Fingertip tactile input device | |
WO2007023850A1 (en) | Key inputting device and electronic device | |
JP6267699B2 (en) | Pushbutton switch with deformable curved contact element | |
CN215451206U (en) | Movable member and input device | |
US7919719B2 (en) | Dome contact used in pushbutton switch | |
JP2016081915A (en) | Push switch | |
JP2010015793A (en) | Tact switch | |
JP5459770B2 (en) | Push switch | |
JP2017079133A (en) | Push switch | |
JP5722198B2 (en) | Waterproof pushbutton switch member and electronic device including the same | |
WO2008044764A1 (en) | Operation key structure | |
JP5722199B2 (en) | Waterproof pushbutton switch member and electronic device including the same | |
US20110083950A1 (en) | Multi-directional tact switch | |
WO2021220979A1 (en) | Switch | |
KR200453797Y1 (en) | Metal dome switch assembly for keypad | |
JP2022030891A (en) | switch | |
JP2020095854A (en) | Movable contact and switch using movable contact | |
TWM367410U (en) | Keypad switch with LED | |
KR20040053775A (en) | Miniaturized tact switch | |
TWM408782U (en) | Membrane switch | |
JP2006019056A (en) | Push-button device |
Legal Events
Date | Code | Title | Description |
---|---|---|---|
AS | Assignment |
Owner name: PANASONIC CORPORATION, JAPAN Free format text: ASSIGNMENT OF ASSIGNORS INTEREST;ASSIGNORS:ISHIGAME, AKIRA;YANAI, YASUNORI;REEL/FRAME:027729/0425 Effective date: 20120125 |
|
STCF | Information on status: patent grant |
Free format text: PATENTED CASE |
|
FEPP | Fee payment procedure |
Free format text: PAYOR NUMBER ASSIGNED (ORIGINAL EVENT CODE: ASPN); ENTITY STATUS OF PATENT OWNER: LARGE ENTITY |
|
FEPP | Fee payment procedure |
Free format text: PAYOR NUMBER ASSIGNED (ORIGINAL EVENT CODE: ASPN); ENTITY STATUS OF PATENT OWNER: LARGE ENTITY Free format text: PAYER NUMBER DE-ASSIGNED (ORIGINAL EVENT CODE: RMPN); ENTITY STATUS OF PATENT OWNER: LARGE ENTITY |
|
MAFP | Maintenance fee payment |
Free format text: PAYMENT OF MAINTENANCE FEE, 4TH YEAR, LARGE ENTITY (ORIGINAL EVENT CODE: M1551) Year of fee payment: 4 |
|
FEPP | Fee payment procedure |
Free format text: MAINTENANCE FEE REMINDER MAILED (ORIGINAL EVENT CODE: REM.); ENTITY STATUS OF PATENT OWNER: LARGE ENTITY |
|
LAPS | Lapse for failure to pay maintenance fees |
Free format text: PATENT EXPIRED FOR FAILURE TO PAY MAINTENANCE FEES (ORIGINAL EVENT CODE: EXP.); ENTITY STATUS OF PATENT OWNER: LARGE ENTITY |
|
STCH | Information on status: patent discontinuation |
Free format text: PATENT EXPIRED DUE TO NONPAYMENT OF MAINTENANCE FEES UNDER 37 CFR 1.362 |
|
FP | Lapsed due to failure to pay maintenance fee |
Effective date: 20220415 |